Kirkwood-Buff Thermodynamics Derived from Grand Canonical Molecular Dynamics and DRISM Calculations

The grand canonical ensemble techniques - both Monte Carlo and molecular dynamics - have become very popular in recent years, but no direct link between the number fluctuation results from these simulation methods and a Kirkwood-Buff theory has been established. In this article we look at Kirkwood-Buff integrals computed using thermodynamic averages derived from grand canonical ensemble molecular dynamics simulations and compare them to similar quantities derived from the dielectrically consistent reference interaction site model many-body theory. These calculations will be carried out for three different water models, SPC, SPC/E, and TIP3P.